Configuration
To configure the parameters of the kite models, edit the file data/settings.yaml, or create a copy under a different name and change the name of the active configuration in the file data/system.yaml.
Parameters
The following parameters are used by this package:
system:
log_file: "data/log_8700W_8ms" # filename without extension [replay only]
# use / as path delimiter, even on Windows
log_level: 2 # 0: no logging
time_lapse: 1.0 # relative replay speed
sim_time: 100.0 # simulation time [sim only]
segments: 6 # number of tether segments
sample_freq: 20 # sample frequency in Hz
zoom: 0.03 # zoom factor for the system view
kite_scale: 3.0 # relative zoom factor for the 4 point kite
fixed_font: "" # name or filepath+filename of alternative fixed pitch font, e.g. Liberation Mono
initial:
l_tether: 150.0 # initial tether length [m]
elevation: 70.8 # initial elevation angle [deg]
v_reel_out: 0.0 # initial reel out speed [m/s]
depower: 25.0 # initial depower settings [%]
solver:
abs_tol: 0.0006 # absolute tolerance of the DAE solver [m, m/s]
rel_tol: 0.001 # relative tolerance of the DAE solver [-]
solver: "DFBDF" # DAE solver, IDA or DFBDF or DImplicitEuler
linear_solver: "GMRES" # can be GMRES or LapackDense or Dense (only for IDA)
max_order: 4 # maximal order, usually between 3 and 5 (IDA and DFBDF)
max_iter: 200 # max number of iterations of the steady-state-solver
steering:
c0: 0.0 # steering offset -0.0032 [-]
c_s: 2.59 # steering coefficient one point model; 2.59 was 0.6
c2_cor: 0.93 # correction factor one point model
k_ds: 1.5 # influence of the depower angle on the steering sensitivity
delta_st: 0.02 # steering increment (when pressing RIGHT)
max_steering: 16.834 # max. steering angle of the side planes for four point model [degrees]
cs_4p: 1.0 # correction factor for the steering coefficient of the four point model
depower:
alpha_d_max: 31.0 # max depower angle [deg]
depower_offset: 23.6 # at rel_depower=0.236 the kite is fully powered [%]
kite:
model: "data/kite.obj" # 3D model of the kite
physical_model: "KPS4" # name of the kite model to use (KPS3 or KPS4)
version: 1 # version of the model to use
mass: 6.2 # kite mass incl. sensor unit [kg]
area: 10.18 # projected kite area [m²]
rel_side_area: 30.6 # relative side area [%]
height: 2.23 # height of the kite [m]
alpha_cl: [-180.0, -160.0, -90.0, -20.0, -10.0, -5.0, 0.0, 20.0, 40.0, 90.0, 160.0, 180.0]
cl_list: [ 0.0, 0.5, 0.0, 0.08, 0.125, 0.15, 0.2, 1.0, 1.0, 0.0, -0.5, 0.0]
alpha_cd: [-180.0, -170.0, -140.0, -90.0, -20.0, 0.0, 20.0, 90.0, 140.0, 170.0, 180.0]
cd_list: [ 0.5, 0.5, 0.5, 1.0, 0.2, 0.1, 0.2, 1.0, 0.5, 0.5, 0.5]
kps4:
width: 5.77 # width of the kite [m]
alpha_zero: 4.0 # should be 4 .. 10 [degrees]
alpha_ztip: 10.0 # [degrees]
m_k: 0.2 # relative nose distance; increasing m_k increases C2 of the turn-rate law
rel_nose_mass: 0.47 # relative nose mass
rel_top_mass: 0.4 # mass of the top particle relative to the sum of top and side particles
kps4_3l:
radius: 2.0 # the radius of the circle shape on which the kite lines, viewed
# from the front [m]
bridle_center_distance: 4.0 # the distance from point the center bridle connection point of
# the middle line to the kite [m]
middle_length: 1.5 # the cord length of the kite in the middle [m]
tip_length: 0.62 # the cord length of the kite at the tips [m]
min_steering_line_distance: 1.0 # the distance between the left and right steering bridle [m]
# line connections on the kite that are closest to each other [m]
width_3l: 4.1 # width of the kite [m]
aero_surfaces: 3 # the number of aerodynamic surfaces to use per mass point [-]
bridle:
d_line: 2.5 # bridle line diameter [mm]
l_bridle: 33.4 # sum of the lengths of the bridle lines [m]
h_bridle: 4.9 # height of bridle [m]
rel_compr_stiffness: 0.25 # relative compression stiffness of the kite springs [-]
rel_damping: 6.0 # relative damping of the kite spring (relative to main tether) [-]
kcu:
kcu_model: "KCU1" # name of the kite control unit model, KCU1 or KCU2
kcu_mass: 8.4 # mass of the kite control unit [kg]
kcu_diameter: 0.4 # diameter of the KCU for drag calculation [m]
power2steer_dist: 1.3 # [m]
depower_drum_diameter: 0.069 # [m]
tape_thickness: 0.0006 # [m]
v_depower: 0.075 # max velocity of depowering in units per second (full range: 1 unit)
v_steering: 0.2 # max velocity of steering in units per second (full range: 2 units)
depower_gain: 3.0 # 3.0 means: more than 33% error -> full speed
steering_gain: 3.0
tether:
d_tether: 4 # tether diameter [mm]
cd_tether: 0.958 # drag coefficient of the tether
damping: 473.0 # unit damping coefficient [Ns]
c_spring: 614600.0 # unit spring constant coefficient [N]
rho_tether: 724.0 # density of Dyneema [kg/m³]
e_tether: 55000000000.0 # axial tensile modulus of Dyneema (M.B. Ruppert) [Pa]
# SK75: 109 to 132 GPa according to datasheet
winch:
winch_model: "AsyncMachine" # or TorqueControlledMachine
max_force: 4000 # maximal (nominal) tether force; short overload allowed [N]
v_ro_max: 8.0 # maximal reel-out speed [m/s]
v_ro_min: -8.0 # minimal reel-out speed (=max reel-in speed) [m/s]
drum_radius: 0.1615 # radius of the drum [m]
gear_ratio: 6.2 # gear ratio of the winch [-]
inertia_total: 0.204 # total inertia, as seen from the motor/generator [kgm²]
f_coulomb: 122.0 # coulomb friction [N]
c_vf: 30.6 # coefficient for the viscous friction [Ns/m]
environment:
v_wind: 9.51 # wind speed at reference height [m/s]
v_wind_ref: [9.51, 0.0] # wind speed vector at reference height [m/s]
temp_ref: 15.0 # temperature at reference height [°C]
height_gnd: 0.0 # height of groundstation above see level [m]
h_ref: 6.0 # reference height for the wind speed [m]
rho_0: 1.225 # air density at zero height and 15 °C [kg/m³]
alpha: 0.08163 # exponent of the wind profile law
z0: 0.0002 # surface roughness [m]
profile_law: 3 # 1=EXP, 2=LOG, 3=EXPLOG, 4=FAST_EXP, 5=FAST_LOG, 6=FAST_EXPLOG
# the following parameters are for calculating the turbulent wind field using the Mann model
use_turbulence: 0.0 # turbulence intensity relative to Cabauw, NL
v_wind_gnds: [3.483, 5.324, 8.163] # wind speeds at ref height for calculating the turbulent wind field [m/s]
avg_height: 200.0 # average height during reel out [m]
rel_turbs: [0.342, 0.465, 0.583] # relative turbulence at the v_wind_gnds
i_ref: 0.14 # is the expected value of the turbulence intensity at 15 m/s.
v_ref: 42.9 # five times the average wind speed in m/s at hub height over the full year [m/s]
# Cabauw: 8.5863 m/s * 5.0 = 42.9 m/s
height_step: 2.0 # use a grid with 2m resolution in z direction [m]
grid_step: 2.0 # grid resolution in x and y direction [m]